Some medicants, notably insulin, are administered in small quantities at regular intervals. To reduce the disadvantages inherent in administration of relatively large medicament doses intermittently, the suggestion has been made to employ a micropump so that only microliter quantities of the medicament are introduced at any one moment. The amounts delivered are frequently measured by a reading of the pumping rate, e.g., by counting the pump pulses of the micropump delivery system (Reference is made to U.S. Pat. No. 3,963,380 for detailed discussion of a micropump adapted to deliver small quantities of medicament.)
Use of a micropump for medicament delivery essentially presupposes that the medicament is removed from a reservoir. Manifestly, a reservoir whose level can be read directly with great accuracy would be a desirable adjunct for micropump delivery of a medicament.